Coral reefs grow best in water of what temperature and depth?
- A30–35 °C and more than 100 m deep
- B5–10 °C at any depth
- C10–15 °C and 100–200 m deep
- D23–29 °C and less than 50 m deep
Show answer and explanation
Correct answer: (d) 23–29 °C and less than 50 m deep
Explanation
Corals need warm (23–29 °C), shallow (under 50 m), clear and steadily salty water. A reef is built by coral polyps living with zooxanthellae algae.